1. Field
Various features pertain to wireless communication systems, and at least some features pertain to devices and methods for improving transmission performance in a wireless network using a plurality of network interfaces for communicating data between a client terminal and proxy device.
2. Background
Client terminals, such as laptop computers, personal digital assistant devices, mobile or cellular phones, or any other device with a processor, that communicate with other devices through wireless signals are becoming increasingly popular. Client terminals typically utilize various channels for different modes of operation. With consumers using powerful applications that run on the client terminals and often require nearly continuous network access, conserving network resources such as bandwidth becomes increasingly important. At the same time, client terminals often have a limited power source (e.g., rechargeable battery pack) and, consequently, may operate in various modes that may assist in extending the operating life of a client terminal between recharging.
A conventional client terminal may operate in one of several modes depending on the communication standard being implemented in a wireless network. For example, Wideband Code Division Multiple Access (WCDMA), the client terminal can be in a Radio Resource Control (RRC) idle mode or connected mode. In the idle mode, no radio resources are available for use in communications. Instead, client terminal periodically monitors one or more control channels, such as the paging channel (PCH), in case the wireless network sends a paging message and/or a control/overhead message. Paging messages may instruct the client terminal to request radio resources to receive an incoming data message. Control/overhead messages carry system information and other information for the client terminal.
If the client terminal desires to make a call or receives a page notification for an incoming call, it requests radio resources to operate in RRC connected mode from the wireless network before proceeding to make or accept the call. In the RRC connected mode, the client terminal can operate in several states which vary in terms of the amount of data communicated, power consumption and available resources. The several states of the RRC connected mode may include, for example, UTRAN Registration Area Paging Channel (URA_PCH), Cell Paging Channel (CELL_PCH), Cell Dedicated Channel (CELL_DCH) and Cell Forward Access Channel (CELL_FACH).
The URA_PCH and CELL_PCH states are similar to the idle mode. For example, the client terminal operating in the CELL_PCH and/or the URA_PCH monitors paging channels periodically and cannot transmit any control or data packets to the wireless network. However, unlike the idle mode, the client terminal has radio resources which are assigned but preserved. The client terminal's power consumption in these states is quite minimal, similar to the idle mode power consumption.
The CELL_DCH and CELL_FACH are two states where the client terminal actively transmits data to and receives data from the wireless network. In the CELL_DCH state, dedicated resources are assigned to the client terminal. In the CELL_FACH state, the client terminal uses common resources (e.g., channels) shared by other terminals in a common cell. Unlike the idle mode, URA_PCH and CELL_PCH states, where the client terminal only periodically monitors paging and/or control/overhead channels, the client terminal operating in the CELL_DCH or CELL_FACH state is continuously monitoring data and control channels for a significant portion of its connection period. Therefore, these two states are responsible for most of the power consumption in the client terminal. The CELL_FACH state operates as a transition state between the idle mode and the CELL_DCH state and typically consumes less power than the CELL_DCH state.
Many of the “always on” applications that run on modern client terminals utilize internet or other network connectivity on a substantially continuous basis, which may inhibit the client terminal from operating in idle mode. For example, instant messaging applications, voice over IP (VOIP) applications, push email, and other connected program applications are typically active, even when such applications are running in the background. With one or more such applications running, the client device may transmit and/or receive several IP packets per time period (e.g., minute) to keep the connection to the servers on the internet active. Such low-rate data communications may require a connected mode in which the client terminal may actively transmit and receive data from the wireless network. Typically, such low-rate data communications are carried out in a transition state of the connected mode (e.g., CELL_FACH state) utilizing shared channels for transmitting data to the wireless network from the client terminal, which shared channels can be relatively slow and are conventionally not well-suited to managing a large number of client terminals.
Therefore, there is a need for a solution that enables resource-efficient communications between a client terminal and a wireless network when the client terminal is operating in a transition state.